METHODOLOGICAL APPROACHES TO DETERMINING THE NOISE QUALITY FACTOR

Abstract

The intensive use of various types of information processing equipment in all spheres of human activity has become commonplace today. At the same time, the operation of any information processing equipment leads to the emergence of a certain set of information leakage through technical channels. One of the most common types of information leakage through technical channels is the channel formed due to compromising emanations and electromagnetic interference (TEMPEST). To prevent information leakage through these technical channels, passive or active protection measures are employed. A combination of passive and active information protection measures may also be applied. Passive protection involves complete electromagnetic shielding of premises and/or information processing equipment, partial shielding of individual components of the equipment, shielding of electrical circuits directly connected to the equipment, and installation of filters in these circuits. Active information protection measures are implemented through the use of generators producing radiated and conducted electromagnetic masking noise. From a practical perspective, active information protection offers several advantages over passive protection, namely: information processing equipment employing passive protection has larger overall dimensions and greater weight; in the case of electromagnetic shielding, ensuring adequate cooling of internal functional units becomes more challenging; modernization of information processing equipment employing passive protection (integration of new components from other manufacturers with different mechanical designs or incorporation of components supporting new interfaces) generally requires modification of the electromagnetic shielding structure; electromagnetic shielding structures invariably include conductive gaskets and movable structural elements that are subject to wear during equipment operation, resulting in degradation of shielding effectiveness and, consequently, a reduction in the level of information protection. Thus, from the perspective of technological complexity, active information protection is easier to implement than passive protection. In general, for active information protection, the following characteristics and parameters of protective noise generators are standardized: operating frequency range, noise power spectral density, interspectral correlation coefficient, and noise quality factor. From a methodological perspective, one of the most challenging tasks is the determination of the noise quality factor as a parameter of protective noise generators. The purpose of this paper is to systematize and provide an analytical review of methodological approaches to determining the protective noise quality factor and to identify directions for their further improvement.